import pandas as pd
import numpy as np
import timeit
df = pd.DataFrame(np.random.randn(10000, 4), columns=list('ABCD'))


class Solution:
    def f(data):
        for k in data:
            print(k)
            if k<0:
                return False
        return True
    def f1(self):
        data =[1,-1,2]
        a =f(data)
        return 1

s = Solution()
print(s.f1())
